<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<script type="text/javascript">
			var num = 1;
			var obj = {};
			var obj2 = Object.create(null)
			document.write(num);
			document.write(obj);
			// document.write(obj2); // 没有原型，没有toString方法，转换不成字符串
		</script>
	</body>
</html>
